Target Surfaces; Hazards Of Use - Johnson 40-6001 Manual De Instrucciones

Measuring Reference
Range
Range is specified between a minimum 20-inches to a maximum of
165-feet with an accuracy of 1/16". Longer ranges will be found by the
instrument but a variance in the accuracy may exist. At night or dusk
the range may be greater than during daylight or if the target has poor
reflective properties.

Target Surfaces

Measuring errors may occur when aiming at surfaces composed of
colorless liquids (e.g. water), glass, Styrofoam or similar semi-permeable
surfaces. Aiming at high gloss surfaces may deflect the laser beam and
lead to measurement errors.

Hazards of Use

Be aware that errors in distance measurements may occur if the
instrument is defective or has been dropped, been misused or modified.
Note
Conduct periodic test measurements to ensure the instrument is measuring
accurately and consistently. This is most important if the instrument has
been exposed to abnormal use. Always confirm accuracy before and
during important measurements. Keep the laser distance measure optic
clean and inspect for damage.
8 ©2010 Johnson Level & Tool - Rev. 1